Marcel van der Linden is Senior Fellow at the International Institute of Social History, Professor of Social Movement History at the University of Amsterdam, and President of the International Social History Association.Magaly Rodríguez García is Assistant Professor at the University of Leuven, Belgium. She has published on human trafficking and child labor, the history and definitions of prostitution, including “Defining Commercial Sexualities, Past and Present” (Ashgate, 2016).